Bottom line: flame-retardant filament is rated by a specific standard and specimen thickness. A UL94 V-0 result at 3.0 mm does not transfer to 1.5 mm. Confirm the standard, thickness, test method and whether the customer accepts filament data or requires finished-part testing.
What to verify
| Item | Detail |
|---|---|
| Standard | UL94, IEC 60695 or customer specification |
| Thickness | Specimen thickness for the rating |
| Level | HB, V-2, V-1, V-0 |
| Direction | Print orientation of the specimen |
| Conditioning | Pre-treatment and ageing |
| Scope | Filament data vs finished part |
Practical notes
- Flame retardants can reduce toughness and flow.
- Dry the filament before printing.
- Ventilate the printing area.
- Confirm the final part if required.
Costly mistakes
- Quoting a rating without thickness.
- Assuming "flame retardant" means non-combustible.
- Applying filament data to a finished part.
- Ignoring print orientation.
- Skipping ventilation.
Buyer / engineer checklist
- Is the standard and thickness defined?
- Is the required level stated?
- Are specimen conditions known?
- Is finished-part testing needed?
- Is ventilation adequate?
Tell us the standard and application and we can help confirm the material route.Compliance support